This invention relates to power divider/combiner circuits, and more particularly to a monolithic broadband power divider/combiner having amplification inherent in the circuit.
Increasing the power-handling capabilities of solid state devices by increasing their size, or by connecting several of them in parallel or in series within a package, can cause problems related to impedance matching, instability, heat dissipation, reliability and yield. This creates the need for power combining of complete amplifiers or oscillators.
In the past power-combining circuits have utilized discrete amplifiers having inputs connected to a power source through a power divider, and outputs connected through a power combiner to a single output port. N-way hybrid power dividers and combiners are well-known in the art. Hybrid power dividers and combiners are actually identical in structure, except their input and output terminals are reversed. Radial and fork hybrid divider/combiner structures are a class of devices first described by Wilkinson, U.S. Pat. No. 3,091,743, which are suitable for narrowband applications. Considerable broadbanding can be achieved by utilizing stepped stripline quarter-wave elements, or by cascading techniques wherein the lines become odd numbers of quarter-wave lengths beyond 1; however, the application and the mathematical relationships of these may become unwieldy.
The distributed amplifier is a high-gain, wideband amplifier which has been used widely in various kinds of electronic equipment. With the advance of modern integrated-circuit technology and with the aid of computers, distributed amplifiers have been designed and built on microstrip with MOSFETs; however, these devices are not suitable for operation in the 10 to 50 GHz region of the microwave spectrum.
In view of the foregoing, it is an object of the present invention to provide improved power divider/combiner circuits for broadband operation.
It is another object of the present invention to provide improved microwave power divider/combiner circuits which are batch processable, monolithic integrated circuits.
Another object of the present invention is to provide improved monolithic power divider/combiner devices for broadband operation in the microwave spectrum and having amplifier circuits inherent in the devices.
It is a more specific object of the present invention to provide an improved power combining circuit having amplification inherent in the divider/combiner devices thereof.